Human skin is an example of a large surface for sensing and actuation. Human skin is able to “sense” many types of signals such as temperature and pressure. Additionally, human skin is capable of many “actuations” as well, such as sweating or goose bumps. Such sensing and actuation has many practical applications, and models or reproductions of the skin's sensing and actuation capabilities have often been attempted. Among other things, sensing and actuation surfaces can be used in medical applications, such as in bio-signal recording interfaces for prosthetics. In any application, the types of sensing and actuation performed by the surface are tailored to the specific needs and desires of the application.
Surfaces with sensing and actuation abilities comparable to those of skin are difficult to achieve. In particular, human skin has a dense distribution of sensing and actuation cells that are interconnected by a large network of nerve fibers. On the other hand, though, in operation, each sensing and actuation cell is individually controlled by the brain. Replicating both the density and the operation of human skin proves challenging.